New Features in Version 4

Home: What's New: If You've Used Version 3: New Features in Version 4

The Geometer's Sketchpad Version 4 contains many improvements and new features. The most important of these are described below, and are also illustrated in the document named HowTo_UpgradeFromV3 contained in the Samples folder.

See also
Sample Documents

Functions and Function Plots

A function defines a method of calculating an output (range) value from an input (domain) value. Version 4 understands functions of the form y = f(x), x = f(y), r = f(theta), and theta = f(r). You can define new functions by choosing New Function from the Graph menu and entering their equation; and you can plot functions, evaluate them in calculations and in other functions, iterate and differentiate them. Function definitions can depend on parameters or other measurements in your sketch, and you can modify existing functions by editing them or by changing the values upon which they depend.

Animation

You can animate any geometric object or parameter, and continue to interact with your sketch while the object is being animated. You can adjust animation speed as precisely as you want, and the animation speed is independent of the speed of your computer. The Motion Controller makes it easy to control animating objects.

Split/Merge

Splitting and merging allow you to modify a sketch in powerful ways. You can merge two points into one, or merge a point onto a path (such as a segment or circle). Similarly, you can split a point apart, or you can split a point from the object on which it's constructed. Splitting and merging allows you to change existing constructions, explore their variations, or correct possible mistakes. Finally, you can merge several text-containing objects into a single caption, or you can merge a text object (caption, measurement, calculation or function) to a point.

See also
Split/Merge

Multiple Pages in Documents

You can add multiple pages to a single document to display several related investigations, or several stages of one investigation. Use Document Options in the File menu to add, remove, copy and rename pages.

Custom Tools

You can create your own tools to easily repeat a particular construction. You can build your own library of custom tools for various purposes. You can use the Script View to inspect, modify, or step through a tool after you've created it.

The Sample documents that come with Sketchpad contain many useful custom tools.

Parameters

Parameters are named numeric values. You can use parameters as part of the definitions of functions and calculations, or of other objects that require values as part of their definition. Changing the value of the parameter then changes the definition of these other objects. (A parameter is to a calculation or a function what an independent point is to a geometric construction—changing the parameter's value changes the result of the calculation or function.) In addition to changing a parameter's value, you can relabel it, animate it, or redefine it as the result of a calculated expression.

See also
Parameters
New Parameter

Multiple and Rectangular Coordinate Systems

Sketches may now contain more than one coordinate system, and each coordinate system may have square, rectangular, or polar units. (A "rectangular" coordinate system is one with different scalings for the x and y axis.) You can rescale a coordinate system's axes by dragging either their unit points or by dragging the unit numbers displayed on the coordinate system's axes.

See also
Coordinate Systems and Axes

Styled Text

You can easily change font size, style and color of selected text objects or of individual characters in captions by using the Text Palette.

See also
Text Palette

Mathematical Notation

You can add symbolic notation, mathematical layout, and geometric and other mathematical symbols to the captions you create.

Color

You can color any object with any color you choose, you can alter the background color of a sketch, and you can even display an object with a color computed from some measurement or calculation in your sketch.

Traces

You can trace any moving geometric object, and traces no longer vanish immediately when you next click in the sketch. Traces remain on the screen until you erase them, or you can use Color Preferences to make them fade away gradually.

Properties Editing

Many of the various editable properties of an object can now be can displayed and modified in a single Properties dialog box.

See also
Properties

Presentation Buttons

You can use a Presentation Button to control the presentation of various actions—animations, movements, hiding and showing objects—in your sketch. You can control what actions occur, whether they happen simultaneously or sequentially, and how long they last.

See also
Presentation Buttons

Link Buttons

You can use a Link Button to move from page to page within a document with multiple pages, or to link to a site on the World Wide Web.

See also
Link Buttons

Online Dynamic Geometry Publishing

You can save sketches in HTML format in order to include interactive Dynamic Geometry sketches on any web pages that you publish.

See also
JavaSketchpad

Editable Calculations

You can use the Calculator not only to create new calculations and functions, but also to edit the expression of existing calculations and functions. Changing a calculation changes any objects defined by that calculation's value in your sketch.

See also
Calculations

Derivatives

You can differentiate any function, and plot the resulting derivative or use it to define other calculations and functions.

See also
Derivative

Iteration

An iteration is a set of images of objects or measurements in your sketch, created by repeatedly applying some rule you specify. You specify the rule by identifying one or more pre-image points to be iterated toward other image points that depend on the pre-images. The iteration consists of repeated images of these pre-image points along with repeated images of objects that depend on the points. Iterations provide a convenient way of repeating certain geometric constructions and transformations, and can be used to create fractals.